From ee30bf233314cc1f40e3afa59ae2ebacf2df1717 Mon Sep 17 00:00:00 2001
From: Martin Holters <martin.holters@hsu-hh.de>
Date: Tue, 19 Nov 2024 10:45:05 +0100
Subject: [PATCH 1/2] =?UTF-8?q?Fix=20`setphase!(::Union{FIRInterpolator,?=
 =?UTF-8?q?=20FIRRational},=20=CF=95)`=20for=20pathological=20cases?=
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For odd number of phases `Nφ` and even length of the filter kernel, the old
code would yield `qidx` above `Nφ`, namely equal tp `Nφ+1`, which would result
in a `BoundsError` during `resample`. Rewrite the code to reduce `qidx` to `1`
in this case and increase `inputDeficit` by one instead. All other
constellations should be unaffected.
---
 src/Filters/stream_filt.jl | 6 +++---
 test/filt_stream.jl        | 4 ++++
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/src/Filters/stream_filt.jl b/src/Filters/stream_filt.jl
index c4a35742a..235c02e42 100644
--- a/src/Filters/stream_filt.jl
+++ b/src/Filters/stream_filt.jl
@@ -218,9 +218,9 @@ end
 
 function setphase!(kernel::Union{FIRInterpolator, FIRRational}, ϕ::Real)
     ϕ >= zero(ϕ) || throw(ArgumentError("ϕ must be >= 0"))
-    (ϕ, xThrowaway) = modf(ϕ)
-    kernel.inputDeficit += round(Int, xThrowaway)
-    kernel.ϕIdx = round(ϕ*(kernel.Nϕ) + 1.0)
+    xThrowaway, ϕIdx = divrem(round(Int, ϕ * kernel.Nϕ), kernel.Nϕ)
+    kernel.inputDeficit += xThrowaway
+    kernel.ϕIdx = ϕIdx + 1
     nothing
 end
 
diff --git a/test/filt_stream.jl b/test/filt_stream.jl
index 51bee9dee..65457f1e0 100644
--- a/test/filt_stream.jl
+++ b/test/filt_stream.jl
@@ -361,3 +361,7 @@ end
         test_rational(h, x, interpolation)
     end
 end
+
+# check that these don't throw; the output should actually probably be longer
+@test resample(1:2, 3, [zeros(2); 1; zeros(3)]) == [1, 0, 0, 2] # [1, 0, 0, 2, 0, 0]
+@test resample(1:2, 3//2, [zeros(2); 1; zeros(3)]) == [1, 0] # [1, 0, 0]

From 4e6d621555fd5d6ddf7b76a58f4838c60ff10dbf Mon Sep 17 00:00:00 2001
From: Martin Holters <martin.holters@hsu-hh.de>
Date: Tue, 19 Nov 2024 16:45:04 +0100
Subject: [PATCH 2/2] =?UTF-8?q?Fix=20`setphase!(::FIRArbitrary,=20=CF=95)`?=
 =?UTF-8?q?=20similarly?=
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Here, the problem is less severe as it requires an explcit call to `setphase!`
with a problematic phase which cannot be hit within normal `resample`
operation.
---
 src/Filters/stream_filt.jl | 2 +-
 test/filt_stream.jl        | 8 ++++++++
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/src/Filters/stream_filt.jl b/src/Filters/stream_filt.jl
index 235c02e42..10d424ce6 100644
--- a/src/Filters/stream_filt.jl
+++ b/src/Filters/stream_filt.jl
@@ -229,7 +229,7 @@ function setphase!(kernel::FIRArbitrary, ϕ::Real)
     (ϕ, xThrowaway) = modf(ϕ)
     kernel.inputDeficit += round(Int, xThrowaway)
     kernel.ϕAccumulator = ϕ*(kernel.Nϕ) + 1.0
-    kernel.ϕIdx         = round(kernel.ϕAccumulator)
+    kernel.ϕIdx         = floor(kernel.ϕAccumulator)
     kernel.α            = modf(kernel.ϕAccumulator)[1]
     nothing
 end
diff --git a/test/filt_stream.jl b/test/filt_stream.jl
index 65457f1e0..1c17e1c03 100644
--- a/test/filt_stream.jl
+++ b/test/filt_stream.jl
@@ -365,3 +365,11 @@ end
 # check that these don't throw; the output should actually probably be longer
 @test resample(1:2, 3, [zeros(2); 1; zeros(3)]) == [1, 0, 0, 2] # [1, 0, 0, 2, 0, 0]
 @test resample(1:2, 3//2, [zeros(2); 1; zeros(3)]) == [1, 0] # [1, 0, 0]
+let H = FIRFilter(2.22)
+    setphase!(H, 0.99)
+    @test length(filt(H, 1:2)) == 3
+end
+let H = FIRFilter(122.2)
+    setphase!(H, 0.99)
+    @test length(filt(H, 1:2)) == 124
+end